The aim of the study was to investigate effect of problem solving method on science-process skills and academic achievement. The sample of the research is consisted of 86 3rd class teacher candidates who attended science teaching programme of Gazi Education Faculty. In this study quasi-experimental design which was pre-test/post-test control group was implemented. While experimental group (41 students) was taught problem solving method, control group (45 students) was taught traditional teaching methods in this study. Science process skills test and electric unit achievement test were administered to both groups before and after the instruction as a pre and post test. Results of study reveal that there is no significant difference between experimental and control groups students’ pre science process skills and pre achievement test scores. Another result of study displays that experimental group students have higher mean scores than control group students in post science process skills and post achievement test.